Safety cartridge for retrievable medical filter

Abstract

The present invention relates to a safety cartridge for a medical filter which can be inserted through a percutaneous access point, via a catheter or introducer, and placed in a blood vessel or other body passage. Filters may have features which are not longitudinally symmetrical, such as anchors or barbs which angle toward one end, or a retrieval hook at only one end. Depending on the physician's selection of the access point, the filter may be introduced to a desired site for treatment from opposing directions. However, it is desirable to introduce the filter with the desired alignment (inserting the desired end in first) regardless of where the selected access point is, and accordingly regardless of which direction of approach to the desired site. As a result, it is desirable to provide a safety cartridge. Cartridges hold filters in an initial compressed shape during storage and insertion into the patient. A safety cartridge may have labels and / or indicators corresponding to which approach direction is selected, showing which end of the cartridge, and so which end of the filter inside the cartridge, to insert first into a catheter or introducer. A safety cartridge may have uniquely shaped first and second ends, which match insertion port(s) on a catheter or introducer which correspond to the selected approach direction. Accordingly, the safety cartridge assists proper orientation of the filter during delivery and treatment.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application is a continuation-in-part of Ser. No. 10 / 285,218, entitled “Vascular Filter with Improved Anchor or Other Position Retention,” filed Oct. 31, 2002; and a continuation-in-part of Ser. No. 10 / 403,470, entitled “Retrievable Medical Filter,” filed Mar. 31, 2003.BACKGROUND AND SUMMARY OF THE INVENTION [0002] 1. Technical Background: [0003] The present invention relates to a safety cartridge for a medical filter which can be placed inside a blood vessel or other body passage for the purpose of intercepting thrombus or particles, which may be optionally retrieved at a later time. [0004] 2. Discussion: [0005] Some types of medical filters are generally known, wherein a single filter element, mesh or member extends across the direction of flow inside a blood vessel. Several features are desirable for medical filters, including non-surgical or percutaneous delivery of the filter to a desired site, and expansion from a prefe...

AI Technical Summary

Benefits of technology

[0012] A safety cartridge may have uniquely shaped first and second ends, which match insertion port(s) on a catheter or introducer which correspond to the selected approach direction. Accordingly, the safety cartridge assists proper orientation of the filter during delivery and treatment.

[0014] Medical filters generally have three types: permanent, temporary or retrievable. A permanent filter is intended for permanent implantation, and a temporary filter is intended for temporary implantation followed by retrieval. In contrast, a retrievable filter offers the physician the option of implanting the filter without initially deciding at that time whether the filter will eventually be retrieved or is to remain permanently. A retrievable filter thus offers the greatest flexibility of medical treatment.

[0015] On a temporary or retrievable filter, it is also desirable to provide releasable temporary position stabilizers, to resist a possibility of tilting and to enhance position retention. Some medical filters provide anchors or small barbs, which extend at various angles in radial directions outward from the ribs.

[0017] The filter may preferably have a retrieval structure or hook at one or both ends, of a design that preferably provides multiple hook surfaces for increasing ease of retrieval.

[0020] A medical filter may have a first and second filter section, arranged on either side of a central body section. The body section and the filter sections thus enclose a space. Due to the elongated shape of the medical filter according to the present invention, and the arranging of the first and second section on either side of the body member, the filter has an enhanced filtering effect. In other words, two filtering structures have been created for intercepting thrombus, particulates or other matter moving inside the blood vessel or other body passage.

[0021] Filters may also have, when seen in an axial or longitudinal direction, filter sections with the shape of a regular polygon, providing several smaller filtering “cells.” The filter sections, as arranged according to an embodiment described above on either side of the tubular body section, may be identical in shape, thereby enhancing the simplicity of the medical filter according to the present invention.

Problems solved by technology

In addition, a medical filter should preferably have a design whereby the filter is stable in the vessel, such that the filter has little or no tendency to “tilt” and may become less effective in capturing thrombus.

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